Novel compounds for new therapeutic interventions are needed for many areas of medicine and disease treatment. For example, chronic and acute inflammatory conditions form the basis for diseases affecting all organ systems including, but not limited to, asthma, acute inflammatory diseases, vascular inflammatory disease, chronic inflammation, atherosclerosis, angiopathy, myocarditis, nephritis, Crohn's disease, arthritis, type I and II diabetes and associated vascular pathologies. The incidence of these inflammatory conditions is on the rise in the population as a whole, with diabetes alone affecting 16 million people. Therefore, synthesis of novel compounds leads to new possibilities for discovery of novel therapeutic interventions.
While inflammation in and of itself is a normal immune response, chronic inflammation leads to complications and ongoing system damage due to the interactions of unknown cellular factors. In particular, chronic inflammation can cause endothelial damage resulting in vascular complications. Coronary artery, cerbrovascular and peripheral vascular disease resulting from atherosclerotic and thromboembolic macroangiopathy are the primary causes of mortality in chronic inflammatory diseases.
Many humans and animals have limited lifespans and lifestyles because of conditions relating to lifestyle choices, such as diet and exercise, or because of genetic predispositions to develop a disease. For example, vascular smooth muscle cell proliferation is a common consequence of endothelial injury and is believed to be an early pathogenetic event in the formation of atherosclerotic plaques or complications related to vascular injury or as a result surgical interventions. Abnormal vascular smooth muscle cell (SMC) proliferation is thought to contribute to the pathogenesis of vascular occlusive lesions, including arteriosclerosis, atherosclerosis, restenosis, and graft atherosclerosis after organ transplantation.
Percutaneous coronary artery intervention (PTCA) procedures are the most common in-patient hospital procedure in the United States. According to the American Heart Association, about one-third of the patients that undergo balloon angioplasty have restenosis of the widened segment of the vessel within approximately 6 months. It may be necessary to perform another angioplasty or coronary artery bypass surgery on restenosed arteries. A key feature of restenosis is an injury response that results in activation of an inflammatory cascade and remodeling of the cells both inside and outside the carotid artery wall. This includes excessive growth of connective tissue and smooth muscle into the lumen of the artery known as neointimal hyperplasia. Currently there are no effective pharmacological treatments available that control the pathogenesis of vascular occlusive lesions, such as, but not limited to, arteriosclerosis, atherosclerosis, restenosis, and graft atherosclerosis after organ transplantation. Identification of effective therapeutics with minimal side effects will restore quality of life without requiring additional surgical procedures such as coronary artery bypass surgery.
Control or modulation of factors produced by the body in response to injury, surgery, metabolic factors or loss of control of in feedback mechanisms, leading to too much or too little of a factor has long been the goal of administering pharmacological agents. One disease that rapidly growing in the industrialized countries is the occurrence of diabetes and all of its attendant sequellae. One of the factors important in the damage associated with diabetes is the presence of glycated proteins.
Glycated proteins and advanced glycation end products (AGE) contribute to cellular damage, particularly, diabetic tissue injury, by at least by two major mechanisms: modulation of cellular functions through interactions with specific cell surface receptors; and alteration of the extracellular matrix leading to the formation of protein cross-links. Studies suggest that glycated protein and AGE interactions with cells may promote inflammatory processes and oxidative cellular injury. AGE increases lipoprotein oxidizability and atherogenicity. Its binding to matrix proteins induces synthesis of cytokines and activates cellular messengers. Diseases where glycated protein and AGE accumulation is a suspected etiological factor include vascular complications of diabetes, microangiopathies, renal insufficiency and Alzheimer's disease.
The exact mechanisms by which high plasma glucose, as seen in diabetes, causes microvascular damage are not completely understood. One potential mechanism by which hyperglycemia can be linked to microangiopathies is through the process of non-enzymatic glycation of critical proteins. Non-enzymatic glycation, i.e., the linking of proteins with glucose, leads to the formation of glycated proteins. The first step in this glycation pathway involves the non-enzymatic condensation of glucose with free amino groups in the protein, primarily the epsilon-amino groups of lysine residues, forming the Amadori adducts. These early glycation products can undergo further reactions such as rearrangements, dehydration and condensations to form irreversible advanced glycation end products (AGE). These are a highly reactive group of molecules whose interaction with specific receptors on the cell-surface which are thought to lead to pathogenic outcomes.
Other major area of disease of where treatments are needed and for which adequate and effective therapies do not exist are cellular proliferative disorders, or disorders caused by unwanted or unintended cellular growth. As mentioned, smooth muscle cell (SMC) hyperplasia is a major event in the development of atherosclerosis and is also responsible for the significant number of failure rates following vascular procedures such as angioplasty, stent implantation and coronary artery bypass surgery. In the normal vessel, SMC are quiescent, but they proliferate when damage to the endothelium occurs. Naturally occurring growth modulators, many of which are derived from the endothelium, tightly control SMC proliferation in vivo. When the control becomes unregulated, a pathological state is induced in the subject.
Another major area of unwanted cellular growth, that is unchecked by the body's regulatory systems, is cancer or oncological conditions. Many therapies have been used and are being used in an effort to restore health or at least stop the unwanted cell growth. Many times, therapeutic agents can have an effect individually, but often, therapeutic regimes require combinations of different pharmacological agents with treatments such as surgery or radiation.
There is a present need for treatments of chronic or acute diseases, such as atherosclerosis, unwanted cellular growth or cellular proliferation, diabetes, inflammatory conditions and vascular occlusive pathologic conditions. Because of occurrence is frequent, the currently available treatments are costly and the conditions are refractory to many pharmacological therapies. The mechanisms involved in the control or prevention of such diseases are not clear and there exists a need for preventive and therapeutic treatments of these and other diseases. Thus, what is presently needed are novel compounds that find utility in methods and compositions for treatment and prevention of chronic and acute diseases, to which the present invention is directed.